THE WATER SUPPLY. 91 



sometimes succumb. Unlike solid food, liquids are at once 

 absorbed, passing direct into the circulation; hence the- 

 water has a more or less effect on the quality of the milk. 



Drinking ponds. The formation of drinking ponds is 

 pretty much the same, whatever the soil may be. They are 

 usually of a circular or quadrangular shape, the latter for 

 preference ; for moderately sized fields, a width of eighteen 

 to twenty-one feet will be sufficient. The better plan is to* 

 commence the excavation at the lowest lip of the future 

 pond, with a slope for the first three yards of one vertical 

 to four horizontal, and for the next two yards, one vertical 

 to three horizontal ; this will give a depth of six feet at 

 the lowest. The best material is a layer of well made 

 concrete, consisting of hydraulic lime and broken stone, of 

 from nine to sixteen inches thick, according to the nature of 

 the soil. This is spread over the surface of the excava- 

 tion, and the top surface is finished with a layer of fine 

 stuff. When carefully prepared it sets immediately, and is 

 perfectly impervious to water, and is little disturbed by the 

 hoofs of stock which come to drink. To prevent the fraying 

 and wearing away of the edge of the concrete on the side 

 used by the cattle, a stone curb 16 inches deep and 4 

 inches thick should be firmly bedded in the soil, the top of 

 which should be level with the land. The inner side forms 

 a ground for the concrete, and insures a strong and durable 

 job. The sides as well as the bottom of the pond, 

 must be made impervious to water by a facing of stone or 

 brick set in cement, or hydraulic lime, or it may be faced 

 with nine to fifteen inches of concrete ; this is best done 

 after the bottom of the pond has been covered. A founda- 

 tion for the side walls is necessary ; this should be sixteen 



